Both Polypodiaceae

Polypodium scouleri vs Zealandia pustulata

These two are not on this page because a keyword tool suggested them. They are here because our own identification model genuinely mistook one for the other, on real photographs, 3 times. We publish the rate, and then we tell you what actually separates them.

Confused 3x by our model Method published

Side by sidefigs. a and b

Polypodium scouleri, photographed by James H. Thomas
fig. a James H. Thomas, CC BY 4.0

Polypodium scouleri

leathery polypody
Zealandia pustulata, photographed by Jon Sullivan
fig. b Jon Sullivan, CC BY 4.0

Zealandia pustulata

hound's tongue fern

How often our model gets it wrong measured, not estimated

When the plant was The model said How often
Polypodium scouleri Zealandia pustulata 3 of 20 (15%)

The confusion runs one way only. The model mistakes Polypodium scouleri for Zealandia pustulata, but not the reverse.

Measured on 38,949 openly licensed, research-grade photographs. Full method and dataset.

What actually separates themon the record

Family Both Polypodiaceae. The family does not separate them.
Genus Polypodium versus Zealandia.

What we do not have yet: the diagnostic morphological character that a botanist would key on, from a source we can cite. We are not going to invent one. Until we have it, this page tells you the two are genuinely confusable, how often, and what the taxonomy and the flowering data do and do not settle.

Both recordsfull pages